Microlens arrays for parallel micropatterning

Abstract

Disclosed herein are systems and methods for using microlens arrays for parallel micropatterning of features. A method includes emitting a laser beam providing the laser beam to a lenslet array including a plurality of lenslets, and generating, from the laser beam, a plurality of laser sub-beams using the lenslet array. Each one of the plurality of laser sub-beams is generated by a corresponding one of the plurality of lenslets. Each lenslet of the plurality of lenslets has the same shape.

What is claimed is: 
     
       1. A method comprising:
 emitting a laser beam; 
 providing the laser beam to a lenslet array through a beam homogenizer, the lenslet array comprising a plurality of lenslets, wherein:
 each lenslet of the plurality of lenslets has a same shape, 
 the lenslet array is positioned on an exit window of the beam homogenizer, and 
 the beam homogenizer shapes the laser beam such that each lenslet receives a respective portion of the laser beam with approximately a same energy and beam profile; and 
 
 generating, from the laser beam, a plurality of laser sub-beams using the lenslet array, each one of the plurality of laser sub-beams being generated by a corresponding one of the plurality of lenslets. 
 
     
     
       2. The method of  claim 1 , further comprising:
 directing the plurality of laser sub-beams toward a substrate to generate or modify a plurality of features on the substrate in parallel, wherein each one of the plurality of laser sub-beams generates or modifies a corresponding one of the plurality of features on the substrate. 
 
     
     
       3. The method of  claim 2 , wherein directing the plurality of laser sub-beams toward the substrate to generate or modify the plurality of features on the substrate in parallel comprises:
 moving at least one of the lenslet array or the substrate such that a focal point of each lenslet of the plurality of lenslets is scanned in a scanning pattern on a material formed on the substrate. 
 
     
     
       4. The method of  claim 3 , wherein the scanning pattern comprises a plurality of concentric circles. 
     
     
       5. The method of  claim 3 , wherein the scanning pattern comprises a spiral. 
     
     
       6. The method of  claim 2 , wherein the plurality of features is formed by two-photon polymerization of a material formed on the substrate. 
     
     
       7. The method of  claim 1 , further comprising:
 directing the plurality of laser sub-beams toward a wafer to generate or modify a plurality of holes through the wafer in parallel, wherein each one of the plurality of laser sub-beams generates or modifies a corresponding one of the plurality of holes through the wafer. 
 
     
     
       8. The method of  claim 7 , wherein directing the plurality of laser sub-beams toward the wafer to generate or modify the plurality of holes through the wafer in parallel comprises:
 positioning at least one of the lenslet array or the wafer such that a focal point of each lenslet of the plurality of lenslets is formed on the wafer. 
 
     
     
       9. The method of  claim 8 , wherein a cross-section of each of the holes has a round shape. 
     
     
       10. The method of  claim 8 , wherein a cross-section of each of the holes has a parallelogram shape. 
     
     
       11. The method of  claim 8 , wherein a pitch of the holes is larger than a pitch of a plurality of mesa shapes that are formed adjacent to a surface of the wafer, wherein each mesa forms a separate light-emitting diode, and wherein the method further comprises maintaining an alignment between the plurality of holes and the plurality of mesas while the plurality of holes is generated or modified by the plurality of laser sub-beams. 
     
     
       12. The method of  claim 1 , further comprising:
 directing the plurality of laser sub-beams toward a silicon substrate to generate or modify a plurality of holes in parallel through a metal layer that is formed on a surface of the silicon substrate, wherein each one of the plurality of laser sub-beams generates or modifies a corresponding one of the plurality of holes through the metal layer. 
 
     
     
       13. The method of  claim 12 , wherein directing the plurality of laser sub-beams toward the silicon substrate to generate or modify the plurality of holes in parallel through the metal layer comprises:
 positioning at least one of the lenslet array or the silicon substrate such that a focal point of each lenslet of the plurality of lenslets is formed on the metal layer. 
 
     
     
       14. The method of  claim 13 , further comprising applying a solution to a remaining portion of the metal layer to create an array of silicon nanowires through metal-assisted chemical etching of a portion of the silicon substrate that is aligned with the remaining portion of the metal layer. 
     
     
       15. The method of  claim 1 , further comprising:
 directing the plurality of laser sub-beams toward an array of light-emitting diodes to generate or modify a plurality of optical elements in parallel in an elastomeric material or a photoresist that is formed on a surface of the array of light-emitting diodes, wherein each one of the plurality of laser sub-beams generates or modifies a corresponding one of the plurality of optical elements in the elastomeric material or the photoresist. 
 
     
     
       16. The method of  claim 15 , wherein directing the plurality of laser sub-beams toward the array of light-emitting diodes to generate or modify the plurality of optical elements in parallel in the elastomeric material or the photoresist comprises:
 positioning at least one of the lenslet array or the array of light-emitting diodes such that a focal point of each lenslet of the plurality of lenslets is formed on the elastomeric material or the photoresist that is formed on the surface of the array of light-emitting diodes. 
 
     
     
       17. The method of  claim 1 , wherein the laser beam is a pulsed laser beam, and the laser beam is shaped by the beam homogenizer to have a flat-top profile. 
     
     
       18. A system comprising:
 a laser that is configured to emit a laser beam; 
 a beam homogenizer that is configured to shape the laser beam to have a flat-top profile; and 
 a lenslet array comprising a plurality of lenslets, wherein:
 the lenslet array is positioned on an exit window of the beam homogenizer, 
 each lenslet of the plurality of lenslets has a same shape, 
 the flat-top profile causes each lenslet to receive a respective portion of the laser beam with approximately a same energy and beam profile, and 
 the lenslet array is configured to generate a plurality of laser sub-beams from the laser beam, each one of the plurality of lenslets being configured to generate a corresponding one of the plurality of laser sub-beams. 
 
 
     
     
       19. The system of  claim 18 , further comprising:
 a beam confiner that is arranged between the laser and the beam homogenizer. 
 
     
     
       20. The system of  claim 19 , wherein the beam confiner is configured to collimate the laser beam.